Indonesian authorities said five people died as the quakes struck, two from heart attacks and three of shock. At least another seven were injured, including a child in critical condition after falling from a tree.

The Indonesian island of Simeulue was closest to the earthquake.

Authorities say an 80-centimetre wave washed up on its shores.

Indonesian president Susilo Bambang Yudhoyono sent in a team of eight senior government officials to assess the situation on the island but their plane was unable to land due to damage to the runway.

For many, the greatest worry came from the revival of memories of the destruction caused by the 2004 tsunami, which was triggered by a magnitude 9.1 earthquake.

When I got to the top of the mountain here there was a Thai man that came up to me right away and he was trembling, physically very upset and he was telling me in Thai about his family that was down the hill but he didn't dare drive down to go looking for them because he didn't know when the wave might hit...

He told me that last time it happened (a tsunami) he was fishing with his friends and when the water started going out he got in his car and drove up into the mountains and the rest of his friends stayed down at the beach and were all killed.

Phuket resident Brent Madison in Thailand

On Simeulue island, residents of the village of Malasin recalled the shock as yesterday's quake struck.

"Everybody in the village rushed outside," 42-year-old resident Asnawi said.

"The ground was shaking very hard and it lasted about five minutes.

"All of us were panicking, children and women were screaming and crying.

"I was outside my house but my 11-year-old daughter and my wife were inside.

"I just screamed at them to get out quickly, because I was so scared that my house would collapse."

The homes in Malasin were newly built after the 2004 tsunami, but they are wooden huts that are still flimsy and vulnerable.

"The ceiling of my house has fallen and some windows were broken," Asnawi said, adding that his home was completely destroyed in the deadly 2004 tsunami, which claimed 170,000 lives in Banda Aceh province, 150 kilometres away.

In Thailand, tourists and residents have also been returning to their homes and hotels after initial evacuations.

Thousands of people were evacuated along the Andaman coast, the same area affected by the 2004 tsunami.

Most waited on hillsides and the roofs of high-rise hotels for a number of hours before the warnings were lifted.

The government system of fixed sirens and loudspeakers put in place after 2004 to urge evacuation seemed to work effectively according to residents.

The mobile phone network crashed due to the volume of calls, but was soon restored.

Malaysia also evacuated residents on the west coast until warnings were lifted.

Geologists say the massive earthquake did not cause widespread destruction because of the movement of the tectonic plates.

The US Geological Survey's Paul Earle says the nature of yesterday's quake prevented a similar catastrophe as the 2004 earthquake and tsunami.

"Fortunately this was far enough off the coast that the shaking on land wasn't enough to cause major damage and then we were also fortunate that the type of earthquake this was, which is a strike-slip earthquake, where the plates slide past each other," he said.

"[Strike-slip quakes] are less prone to creating large tsunamis as we saw here."